Surround audio systems utilize an array of different speakers (also referred to as loudspeakers) that may include one or more drivers in a cabinet. A typical 5.1 or 7.1 surround sound (channel-based) system comprises five or seven speakers along with a subwoofer for low frequency effects (LFE). The speakers are designed and intended to be placed around a listening environment (e.g., room, theatre, auditorium, etc.) and play different channels of the audio program (e.g., front/back, left/right, etc.). The speakers may include different drivers to optimally play different frequencies, such as woofers for lower frequencies, mid-range speakers for mid frequencies, and tweeters for higher frequencies. Newer audio formats, such as the object-based Dolby Atmos system may introduce additional speakers, such as height speakers or reflected sound speakers that provide immersive sound by projecting sound based on height cues in the audio program.
In present channel-based systems, individual speakers are strictly assigned to specific channel feeds from a decoder or directly from the source and are meant to be placed at well-defined locations within the listening environment. Surround sound speakers are typically configured into sets of speaker types with relatively large single or dual-driver units for the side speakers, smaller speakers single-driver units for the front and back locations, a soundbar-type speaker for the central channel, and a large subwoofer for the LFE (.1) channel. Thus, present speaker systems for surround sound systems utilize a number of different speaker types, which are each required to be placed in a particular placement for optimal playback of the program content, which often requires special room configuration and installation routines.
The advent of object and immersive (or adaptive) audio in which channel-based audio is augmented with a spatial presentation of sound utilizes audio objects, which are audio signals with associated parametric descriptions of apparent position (e.g., 3D coordinates), apparent width, and other parameters. Such immersive audio content may be used for many multimedia applications, such as movies, video games, simulators, and can benefit from a flexible configuration and arrangement of speakers within the listening environment. A main advantage of immersive audio systems over traditional channel-based surround sound systems is the accurate representation of audio content around and above the listener as represented at least in part by height cues in the audio content. This however requires the use of specific (e.g., ceiling) speakers to project the height sound components from above a listener's head. Special speaker designs have been developed to allow relatively easy mounting in high locations, but this obviously adds a great deal of complexity and cost in laying out immersive audio speaker systems.
To take advantage of the immersive audio that is provided by the height component, but to not require physically mounted ceiling or high wall speakers, new speaker designs have been introduced that integrate upward-firing drivers to reflect sound off of an upper surface (e.g., ceiling) of a listening environment. This allows a floor standing or wall-mounted speaker to provide both direct and height projected sound into the listening environment. Such a speaker system is described in U.S. application Ser. No. 62/007,354 entitled “Audio Speakers Having Upward-firing Drivers for Reflected Sound Rendering,” filed Jun. 3, 2014, which is hereby incorporated by reference in its entirety. This type of speaker can be used as the only speaker in a surround sound system as each speaker includes both direct (front) and upward-firing drivers, thus providing the side (L/R), front, back and center channel playback functions. Such a speaker is referred to herein as a “front/upward firing speaker” or an “integrated speaker.” If appropriately configured with the proper driver or drivers, it can also function as a subwoofer capable of reproducing low-frequency effects (LFE). Thus, this type of speaker allows a surround sound system to use only one type of speaker, or at most two types, if a separate subwoofer is used.
One potential disadvantage of this type of speaker is its usage as the center channel speaker. A typical surround-sound speaker array uses a single central speaker for playback of primarily dialog content. Such a speaker is intended to be placed centrally and below a television monitor or cinema screen, and is usually packaged as a sound bar or long horizontal enclosure with a number of drivers, such as two to six drivers in a linear array. The integrated front/upward firing speaker is typically configured as a vertical speaker that features a tall profile relative to the base footprint. As such, it is not optimal for placement under a television or monitor. What is needed therefore, is a front/upward firing speaker that can be oriented either vertically or horizontally and transmit its orientation to an audio renderer or decoder and receive updated speaker feeds based on its orientation.
The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be inventions.